Plug injector apparatus



,Nov. 9, 1965 T. w. DIEHL 3,216,500

PLUG INJECTOR APPARATUS Filed Sept. 18, 1962 To cam e I 2 INVENTOR.

Thom 06 14 Dle/l/ gjma w HGENT United States Patent Office Patented Nov.9, 1965 3,216,500 PLUG INJECTOR APPARATUS Thomas W. Diehl, Tulsa, Okla,assignor to The Dow Chemical Company, Midland, Mich., a corporation ofDelaware Filed Sept. 18, 1962, Ser. No. 224,334 4 Claims. 16670) Thisinvention relates to plug injector apparatus and particularly toapparatus used for injecting so-called cementing type plugs into thecasing of earth wells during a well treating operation.

In conventional cementing plug injector apparatus the plug or plugs isusually held in .position in the injector apparatus by means of a pinwhich extends across the apparatus either through or below the plug.Extraction of the pins is often difiicult to accomplish in a timelymanner because the pressures encountered during the cementing or othertreating operation cause the pin to bind as it is being retracted.

Accordingly, a principal object of this invention is to provide animproved plug injector apparatus for use in treating earth wells.

Another object of this invention is to provide an improved, easy toactuate plug injector apparatus for use in treating earth wells.

In accordance with this invention there is provided plug injectorapparatus comprising a hollow cylindrical body section adapted toreceive a plug of the so-called cementing plug type. The plug is axiallyaligned with the longitudinal axis of the body section and is held inposition prior to its release by an arcuate (generally semicircularlyshaped) element which extends across the diameter of the body sectionwith its convex part facing upwardly and supporting the lower .part ofthe plug.

Means are provided for rotating the arcuate element from a positionwhere the elements convex part faces upwardly generally along thelongitudinal axis of the body section to where the arcuate element liesperpendicular to the longitudinal axis of the body section along thewall of the body section. The plug is then forced, by pressure exertedfrom above, down the body section, past the arcuate element and into thewell casing (not shown).

The invention, as well as additional objects and advantages thereof,will best be understood when the following detailed description is readin connection with the accompanying drawing, in which FIG. 1 is a sideelevational view, in section, of injector apparatus made in accordancewith this invent-ion, and

FIG. 2 is an exploded isometric view showing the plug releasingmechanism of the apparatus shown in FIG. 1.

Referring to the drawing, there is shown plug injector apparatus,indicated generally by the numeral 10, which comprises an elongatedgenerally tubular body section 12 which has an upper end cap 14 coupledthereto by means of threads 16. Threads 18 at the lower end of the bodysection provide the means by which a coupling element, such as thecollar 20, couple the injector apparatus to other well head apparatus22, a line 40, a valve 42 and thence to the casing (not shown) of thewell under treatment.

The body section 12 has a first pumpable materials inlet 24 near itsupper end and a second pumpable materials inlet 26 near its lower end.Inlets 24 and 26 are coupled by means of lines 28, 30 and valves 32, 34,respectively, to a line 36 which is coupled to the cement pump asindicated by the numeral 38.

Between the inlets 24, 26, and usually near the lower inlet 26, aredisposed diametrically opposite bores 44, 48. The bore 44 extends onlypart way through the body section from the inner wall 78 thereof. Thebore 48 extends through the wall of the body section and through theboss 46. The bore 48 has a generally circular groove 67 along its wall.A bore 50 extends from the outer surface of the boss 46 to the bore 48.

An arcuate, generally semi-circular shaped plug retaining element 56 isdisposed within the hollow part of the body section, the element 56being coupled to the bores 44, 48 which are axially aligned with oneanother. The retaining element 56 comprises a curved strip of springsteel plus the outwardly extending and axially aligned studs 58, 60. Thestud 58 extends into the bore 44, the depth of the bore-being slightlygreater than the length of the stud 58.

The stud 60 extends into the bore 48 and is coupled to the forked end 66of the plug retainer actuating rod 62. The actuating rod 62 is adaptedto fit slidably within the bore 48, an O ring seal 54 fitting in thegroove 67 in the bore 48 and the aligned groove 68 (see FIG. 2) in therod 62. The rod 62 also has a groove 70 which, when the rod isoperatively aligned in the bore 48, is aligned with the bore 50. Setscrew 52, screwed into the threaded bore 50, extends through the groove68, keeping the rod 62 in the desired position within the bore 48whereby the forked end 66 properly engages the stud 60. A barlike handle65 is secured to the outer end of the rod 62. The handle contains a bore72 through which indexing pin 74 may be inserted to engage the boss 46and hold the retainer element 56 in the plug holding position. Theindexing pin 74 is secured to the handle 65 (see FIG. 1), for example,by means of the small chain 76.

In operation, with the valve 32 closed, the valves 34 and 42 open, and aplug 64 in the body 12 of the apparatus 10 above the retainer element 56(which is in the hold posit-ion), cement or other pumpable material ispumped into the well casing.

When it is desired to drive the plug 64 down the well casing, theretainer element 56 is turned degrees whereby it lies against the ledge63 and thinned wall part 69, more or less out of the path 'of the plug64 as it passes down the apparatus and into the well casing. The plug 64is forced down the apparatus by opening valve 32 and then at leastpartially closing the valve 34 to provide a greater force above the plug64 than exists below it.

Because the retainer element is supported at both ends and is merelymoved out of the path of the plug 64, the movement of the element 56 mayeasily and rapidly be accomplished by rotating the handle 65 through a90 degree are.

The retaining element 56 always remains entirely within the body of theapparatus, thereby eliminating the possibility of the operating pressurewithin the apparatus driving the retaining element from the apparatus assometimes occurred in certain prior art plug injection apparatus.

What is claimed is:

1. Plug injector apparatus for use in earth well cementing or treatingoperations, comprising an elongated generally tubular body sectionhaving open upper and lower ends and inner and outer wall surfaces,means for closing said upper end, means for coupling said lower end toother hollow apparatus, a pumpable materials inlet, said inlet extendingthrough the wall of said body section near the upper end of said bodysection, a pair of axially aligned bores, said bores being disposedbelow said materials inlet and perpendicular to the longitudinal axis ofsaid body section, the longitudinal axis of the bores intersecting thelongitudinal axis of the body section, one of said bores extendingthrough the wall of said body section and the other bore extendingpartially through said body section, a plug retainer-member, saidretainer member being a strap-like metal element which is semicircularin longitudinal cross sectional configuration, the diameter of thestrap-like element being at least approximately the same as the innerdiameter of the body section, and a pair of studs, each of said studsbeing rigidly secured to the outwardly facing part of said strap-likeelement at least near to an end of said element, one of said studsextending into each of said bores whereby said retainer member ispivotable about the longitudinal axis of said axially aligned bores, aretainer member actuating rod, said rod extending through said axiallyaligned bore which extends through said wall and being positivelymechanically coupled to the stud in said bore whereby said retainermember rotates as said actuating rod is rotated, and means for rotatingsaid actuating rod.

2. Apparatus in accordance with claim 1, wherein the inner wall of saidbody section has a recessed part adjacent to said bores which is adaptedto receive said straplike element when said actuator rod is rotated to apredetermined position.

4 3. Apparatus in accordance with claim 1, wherein sealing means isprovided between said actuator rod and the adjacent bore wall.

4. Apparatus in accordance with claim 1, wherein a second pumpablematerials inlet extends through the wall of the body section below saidbores.

References Cited by the Examiner UNITED STATES PATENTS 2,196,652 4/40Baker 166-70 2,615,519 10/52 Carr 166--70 2,620,037 12/52 McClendon 166-70 2,630,179 3/53 Brown 16670 2,664,163 12/53 Sch-mitter 166702,870,842 1/59 Hall 16670 3,125,116 3/64 Schaberg 150104.06

BENJAMIN HERSH, Primary Examiner.

1. PLUG INJECTOR APPARATUS FOR USE IN EARTH WELL CEMENTING OR TREATINGOPERATIONS, COMPRISING AN ELONGATED GENERALLY TUBULAR BODY SECTIONHAVING OPEN UPPER AN LOWER ENDS AND INNER AND OUTER WALL SURFACES, MEANSFOR CLOSING SAID UPPER END, MEANS FOR COUPLING SAID LOWER END TO OTHERHOLLOW APPARATUS, A PUMPABLE MATERIALS INLET, SAID INLET EXTENDINGTHROUGH THE WALL OF SAID BODY SECTION NEAR THE UPPER END OF SAID BODYSECTION, A PAIR OF AXIALLY ALINGED BORES, SAID BORES BEING DISPOSEDBELOW SAID MATERIALS INLET AND PERPENDICULAR TO THE LONGITUDINAL AXIS OFSAID BODY SECTION, THE LONGITUDINAL AXIS OF THE BORES INTERSECTING THELONGITUDINAL AXIS OF THE BODY SECTION ONE OF SAID BORES EXTENDINGTHROUGH THE WALL OF SAID BODY SECTION AND THE OTHER BORE EXTENDINGPARTIALLY THROUGH SAID BODY SECTION, A PLUG RETAINER-MEMBER, SAIDRETAINER MEMBER BEING A STRAP-LIKE METAL ELEMENT WHICH IS SEMICIRCULARIN LONGITUDINAL CROSS SECTIONAL CONFIGURATION, THE DIAMETER OF THESTRAP-LIKE ELEMENT BEING AT LEAST APPROXIMATELY THE SAME AS THE INNERDIAMETER OF THE BODY SECTION, AND A PAIR OF STUDS, EACH OF SAID STUDSBEING RIGIDLY SECURED TO THE OUTWARDLY FACING PART OF SAID STRAP-LIKEELEMENT AT LEAST NEAR TO AN END OF SAID ELEMENT, ONE OF SAID STUDSEXTENDING INTO EACH OF SAID BORES WHEREBY SAID RETAINER MEMBER ISPIVOTABLE ABOUT THE LONGITUDINAL AXIS OF SAID AXIALLY ALIGNED BORES, ARETAINER MEMBER ACUTATING ROD, SAID ROD EXTENDING THROUGH SAID AXIALLYALIGNED BORE WHICH EXTENDS THROUGH SAID WALL AND BEING POSITIVELYMECHANICALLY COUPLED TO THE STUD IN SAID BORE WHEREBY SAID RETAINERMEMBER ROTATES AS SAID ACTUATING ROD IS ROTATED, AND MEANS FOR ROTATINGSAID ACTUATING ROD.